As the majority of the pigs bought of dealers by amateurs are young pigs it may be advisable to state that a pig of the age of eight weeks old should have its two central incisors fully grown. A pig three months old should have all four temporary incisors cut, the two outside ones being more than half as long as the two central incisors.
As the first set of the teeth of a pig like that of a child are merely temporary, and as these give place at fairly definite ages of the owner to permanent ones, it may be well to endeavour to describe as clearly as possible the position and appearance of the temporaries as compared with the permanents. The pig is one of the few animals which is possessed of teeth at its birth; these number eight, two on each side of the upper and lower jaw. It has been suggested that these early teeth are provided to assist the pigling to grasp firmly the sow's teat when in the act of sucking. These eight teeth vary somewhat in length; those pigs which are carried by the sow beyond the usual period of sixteen weeks frequently have longer and even sharper teeth than those of pigs which are born at the usual time. These longer teeth are also sometimes of a dark colour. This is doubtless the origin of the remark commonly made by old-fashioned pigmen that "pigs born with black teeth never do well." This might have been so prior to the discovery that the breaking off the sharp teeth of the newly born pigs frequently saved trouble, and often the life of the little pigs. Pigs whose teeth are discoloured at birth are usually more robust rather than the reverse, since the sow carrying them beyond the allotted time is invariably in a vigorous state of health, and her pigs consequently more fully developed.
When the pig is about a month old, the two central incisors are cut in each jaw, these are two of the four front teeth in each jaw of the pig at a subsequent age. Two temporary molars are also cut on each side of the jaw above and below, with the first temporary molar in each place ready to come through the gum.
At two months the temporary central incisors are fully developed, and the two lateral temporary incisors can be seen in the gums, if they are not already through. All three temporary molars are now about level.
When the pig is about three months old its temporary teeth are all in position, the temporary lateral incisors are through, and nearly as long as the temporary central incisors. Owing to the lengthening of the jaws the two temporary corner teeth which were present at birth will have become further apart. When the pig is about five months, the fourth molar in either jaw shows itself in the gums, then at six months the wolf teeth show between the tusks and the premolars, and the fourth molar is nearly level with the first premolar. The corner incisors and the tusks usually disappear, and are replaced by permanents when the pig is nine months old. The second permanent molar also shows itself. At twelve months the two central temporary incisors give place to the permanents; these last are more square in form than the temporaries, and are thus easily distinguished. The three temporary molars will also be ready for displacement by three permanents. These last will be level with the other permanent molars when the pig is fifteen months. The two lateral incisors will also have given place to permanents. At eighteen months the third permanent molars will be coming through, and at the age of twenty months the pig's teeth are fully developed.
CHAPTER V
SELECTION OF THE BOAR
The hackneyed saying "The sire is half the herd" appears to have a different meaning to varying persons. To some it conveys the idea that the selection of the sire is of far more importance than the selection of the dam because the influence of the sire is so much more powerful than that of the dam on at least the external form and character of the produce. The late Mr. James Howard, who took a particularly keen interest in the breeding of pigs, used to declare that the appearance and form of the young pigs far more generally followed those of the sire than of the dam; whilst the influence of the latter was more shown in the character and constitution of their joint produce; or in other words, that the boar stamped his character to a greater extent on the external points of the young, whilst the sow more strongly influenced the internal parts of the youngsters. It is quite possible that this idea has gained ground to a large extent from the fact that the use of a pure bred sire on ordinary or grade females has been very much more common than the crossing of pure bred females by the ordinary or non-pedigree sire; as also from the far greater numbers of young which each pure bred sire would improve, than would be improved by each pure bred female which might be crossed.
If only for this reason alone, we would always recommend buyers who are desirous of grading up and improving their farm stock to attempt to do this by the purchase or use of the pure bred or improved sire. The original outlay is infinitely less, whilst the immediate results are comparatively longer.
It is scarcely desirable to go further into the question as to the comparative influence on the young of the sire and the dam since our actual knowledge of the subject is by no means large. Indeed, it is at the least doubtful, if by the closest observation any definite opinion on the subject is possible, so great is the difference which varying parents have on the chief characteristics of their joint progeny, and even in the separate specimens which they have procreated. Of course, it is quite possible to breed animals especially well developed or endowed with certain qualities, providing that the parents have been for generations selected because of their possession in a marked degree of those particular qualities sought. It is in this power of prepotency that one of the chief benefits from the use of a pure bred sire or dam arises. By the term pure bred is not meant merely that the names of a certain number of the forbears of the animal shall have been recorded in the register of the breed, but that the animal shall for a certain number of generations have been bred on similar lines so that it shall possess a considerable amount of concentrated blood. This is a point to which sufficient care is not generally given by purchasers of so-called pedigree sires to be used on the ordinary bred or graded stock. The far too common practice is to purchase each boar required from a totally different herd, or from one of quite dissimilar breeding, with the result that there is not the slightest uniformity in the appearance or character of the herd, or of the mature animals when ready for market.